Parents who take long career breaks to look after their children are to be rewarded with £500 in training grants to coax them back into work.

The grants will inevitably be dubbed "mummy bonds" in an echo of the last universal benefit: the £250 "baby bonds" allocated to every newborn child in a savings account introduced in 2002.

The grants will be made to every person who has taken more than five years off work to care for a child or sick relative.

They are to help parents retrain after a spell out of the workforce and to ensure that those who have sacrificed some of their career to caring duties do not slip down the career ladder. Ministers want to reward people - mostly women - for the contribution their caring duties have made to society and make sure they are not disadvantaged when they return to work. The grant will be universal.

The plan, from John Denham's Department for Innovation, Universities and Skills (Dius), will be piloted to test the best way to allocate the grants. It is a feature of the New Opportunities white paper due next week to improve social mobility.

The money will be paid into a skills account rather than in cash and may be used for IT courses, sales and marketing or project and financial training. The funding comes after widespread concerns that women's earnings and careers are damaged after having children. On average women earn 17% less an hour full-time and 41% less part-time than men.